DO THALAMIC LESIONS REALLY CAUSE VERTICAL GAZE PALSIES

Two patients with thalamic infarctions presented with vertical gaze pa lsies. Magnetic resonance imaging (MRI) demonstrated extension of the lesions into the upper midbrain. A common vascular supply to both area s, and the inability of computed tomography (CT) scans to adequately a ssess posterior fossa structures, necessitate MRI of the mesencephalon in the assessment of all patients with vertical gaze dysfunction. The se cases shed further doubt regarding a specific role of the thalamus in control of vertical eye movements.